Anti-IL-17A blocking antibody reduces cyclosporin A-induced relapse in experimental autoimmune encephalomyelitis mice

CKD-506: A novel HDAC6-selective inhibitor that exerts therapeutic effects in a rodent model of multiple sclerosis

Despite advances in therapeutic strategies for multiple sclerosis (MS), the therapy options remain limited with various adverse effects. Here, the therapeutic potential of CKD-506, a novel HDAC6-selective inhibitor, against MS was evaluated in mice with myelin oligodendrocyte glycoprotein35-55 (MOG35-55)-induced experimental autoimmune encephalitis (EAE) under various treatment regimens. CKD-506 exerted prophylactic and therapeutic effects by regulating peripheral immune responses and maintaining blood-brain barrier (BBB) integrity. In MOG35-55-re-stimulated splenocytes, CKD-506 decreased proliferation and downregulated the expression of IFN-γ and IL-17A. CKD-506 downregulated the levels of pro-inflammatory cytokines in the blood of EAE mice. Additionally, CKD-506 decreased the leakage of intravenously administered Evans blue into the spinal cord; CD4+ T cells and CD4-CD11b+CD45+ macrophage/microglia in the spinal cord was also decreased. Moreover, CKD-506 exhibited therapeutic efficacy against MS, even when drug administration was discontinued from day 15 post-EAE induction. Disease exacerbation was not observed when fingolimod was changed to CKD-506 from day 15 post-EAE induction. CKD-506 alleviated depression-like behavior at the pre-symptomatic stage of EAE. In conclusion, CKD-506 exerts therapeutic effects by regulating T cell- and macrophage-mediated peripheral immune responses and strengthening BBB integrity. Our results suggest that CKD-506 is a potential therapeutic agent for MS.

NFAT-Specific Inhibition by dNP2-VIVITAmeliorates Autoimmune Encephalomyelitisby Regulation of Th1 and Th17

Nuclear factor of activated T cells (NFATs) is an important transcription factor for T cell activation and proliferation. Recent studies have highlighted the role of NFATs in regulating the differentiation of effector CD4 T helper (Th) subsets including Th1 and Th17 cells. Because controlling the effector T cell function is important for the treatment of autoimmune diseases, regulation of NFAT functions in T cells would be an important strategy to control the pathogenesis of autoimmune diseases. Here, we demonstrated that an NFAT inhibitory peptide, VIVIT conjugated to dNP2 (dNP2-VIVIT), a blood-brain barrier-permeable peptide, ameliorated experimental autoimmune encephalomyelitis (EAE) by inhibiting Th1 and Th17 cells, but not regulatory T (T_reg) cells. dNP2-VIVIT negatively regulated spinal cord-infiltrating interleukin-17A (IL-17A) and interferon (IFN)-γ-producing CD4⁺ T cells without affecting the number of Foxp3⁺ CD4⁺ T_reg cells, whereas dNP2-VEET or 11R-VIVIT could not significantly inhibit EAE. In comparison with cyclosporin A (CsA), dNP2-VIVIT selectively inhibited Th1 and Th17 differentiation, whereas CsA inhibited the differentiation of all T cell subsets including that of Th2 and T_reg cells. Collectively, this study demonstrated the role of dNP2-VIVIT as a novel agent for the treatment of autoimmune diseases such as multiple sclerosis by regulating the functions of Th1 and Th17 cells.

Novel pathomechanisms in inflammatory neuropathies

Inflammatory neuropathies are rare autoimmune-mediated disorders affecting the peripheral nervous system. Considerable progress has recently been made in understanding pathomechanisms of these disorders which will be essential for developing novel diagnostic and therapeutic strategies in the future. Here, we summarize our current understanding of antigenic targets and the relevance of new immunological concepts for inflammatory neuropathies. In addition, we provide an overview of available animal models of acute and chronic variants and how new diagnostic tools such as magnetic resonance imaging and novel therapeutic candidates will benefit patients with inflammatory neuropathies in the future. This review thus illustrates the gap between pre-clinical and clinical findings and aims to outline future directions of development.

Secukinumab improves psoriasis symptoms in patients with inadequate response to cyclosporine A: A prospective study to evaluate direct switch

There are limited data on the safety and efficacy of switching to secukinumab from cyclosporine A (CyA) in patients with psoriasis. The purpose of the present study was to assess the efficacy and safety of secukinumab for 16 weeks after direct switching from CyA in patients with moderate-to-severe psoriasis. In this multicenter, open-label, phase IV study, 34 patients with moderate-to-severe psoriasis and inadequate response to CyA received secukinumab 300 mg s.c. at baseline and weeks 1, 2, 3, 4, 8 and 12. The primary end-point was ≥75% improvement from baseline in Psoriasis Area and Severity Index score (PASI 75) at week 16. The efficacy of secukinumab treatment was evaluated up to week 16, and adverse events (AE) were monitored during the study. The primary end-point of the PASI 75 response at week 16 was achieved by 82.4% (n = 28) of patients receiving secukinumab. Early improvements were observed with secukinumab, with PASI 50 response of 41.2% at week 2 and PASI 75 response of 44.1% at week 4. AE were observed in 70.6% (n = 24) of patients, and there were no serious AE or deaths reported in the entire study period. Secukinumab showed a favorable safety profile consistent with previous data with no new or unexpected safety signals. The results of the present study show that secukinumab is effective in patients with psoriasis enabling a smooth and safe direct switch from CyA to biological therapy.